Thunder Strike XXL

Thunder Strike XXL is a coin-collecting slot from Booongo that arrived at casinos in late October 2026. The theme is pure electricity: blue lightning crackles across a dark night sky, a big golden lightning bolt badge forms the logo, and a pile of gold coins glows under the jackpot panel. The game uses an unusual tall layout of 3 reels and 5 rows with 15 fixed paylines, and its main attraction is a respin bonus with sticky Thunder Bonus symbols and four fixed jackpots.

Classic Fruit Symbols on a Tall Grid

The regular symbols come straight from the fruit machine tradition. The red 777 is the top symbol and also the Wild: three of them on a line pay 30x the bet, and it substitutes for all symbols except Bonus and Thunder Bonus. Golden bells pay 10x for three, double BAR symbols 8x, and watermelons and grapes 4x. Plums, oranges and lemons return 1x, and the cherries 0.5x for a line of three. Lines pay from left to right, only the highest win per line is counted, and all 15 lines are always active, so the only stake setting is the total bet.

Because the grid is taller than it is wide, the paylines look different from a standard five-reel game. The first five lines run straight across each of the five rows, while the other ten zigzag up and down between the rows, so a winning line can bend across the whole height of the screen. Three matching symbols on a line from the left are always needed for a win.

Bonus Coins and the Thunder Bonus Symbol

Two special symbols drive everything else. The golden Bonus coin lands only on reels 1 and 3 and carries a cash value. In the bonus round these values are x1, x2, x3, x4, x5, x6 or x8 the bet, and the coins can also show one of the jackpot labels. The blue Thunder Bonus symbol lands only on the middle reel 2 and is the trigger for the game’s signature mechanic.

How the Thunder Strike Feature Works

When a Thunder Bonus symbol appears together with any Bonus coin, the Thunder Strike Feature fires. Lightning flows from the middle reel across the grid and collects the values of every Bonus symbol on screen, including the Mini, Minor, Major and Grand jackpot coins. The collected total is added to the win for that spin in the main game, or to the total win when it happens during the bonus round. This means a single base game spin can pay a solid prize even without a full bonus trigger.

The Bonus Game: a Hold and Spin Round

The Bonus Game starts when at least one Bonus symbol is visible on each of the three reels. It plays like a classic Hold and Spin feature. The grid clears, only Bonus and Thunder Bonus symbols can land, and you get 3 respins. Every new symbol that lands resets the counter back to 3, and the round continues until the respins run out.

The twist is in the middle reel. Thunder Bonus symbols stick on reel 2 for the rest of the round, and each one keeps absorbing coin values whenever the Thunder Strike Feature is triggered. The intro screen promises up to 5 Thunder Bonus symbols in the Bonus Game, so a full middle column of lightning symbols can multiply the collecting power. When the round ends, the amounts stored in all Thunder Bonus symbols are added to the total win.

Since every new symbol brings the respins back to three, a good round can last much longer than the starting three spins. The grid has 15 positions, and each coin that sticks makes the next one more valuable when lightning is on the middle reel, so the second half of a long round is usually where the biggest sums are built.

Four Fixed Jackpots

The jackpot panel on the left lists four prizes that scale with the bet. A Bonus symbol with a jackpot label can appear at random during the Bonus Game and awards the matching prize: Mini 15x, Minor 30x, Major 100x and Grand 1,000x the bet. The jackpot coins also count for the Thunder Strike Feature, so their values are included whenever the lightning collects.

Pile of Gold Feature

There is an extra way into the bonus in the main game. Any Bonus coin that lands gives a chance to trigger the Pile of Gold Feature. When it activates, the game adds enough Bonus and Thunder Bonus symbols to the reels to start the Bonus Game straight away. It is a random event, so you may see a spin with only one or two coins suddenly turn into the respin round.

Buy Options

The green BONUS button below the jackpot panel opens the buy menu, where this option is allowed. The standard Bonus Game costs 70x the bet and starts with one or more Thunder Bonus symbols already in place. The Super Bonus Game costs 200x the bet and guarantees three or more Thunder Bonus symbols from the first respin.

A Super Bonus Game in Action

When the Super Bonus is bought, a shower of coins opens the round, then the grid fills with gold coins, a Minor jackpot coin and a stack of Thunder Bonus symbols in the middle. With three lightning symbols collecting at once, the values on reel 2 climb with every new coin, first to 36x, then 41x, 45x and 49x, before the round closes and the stored amounts are added together. That run ended with a total win of 159x the bet, which shows how quickly the stacked Thunder Bonus symbols can add up.

The interface is clear and easy to use. The round green button spins, holding it switches to turbo, the A icon opens autoplay and the double arrow speeds up the reels. The information page explains every symbol and feature with pictures, and it lists all 15 paylines.

Playing Tips

Keep an eye on the middle reel in the base game. A Thunder Bonus symbol there is the moment to watch for coins on reels 1 and 3, as any combination pays out immediately through the Thunder Strike Feature. If you consider the buy options, remember that the 200x Super version costs almost three times as much as the standard one, and that the extra value comes from the guaranteed Thunder Bonus symbols rather than from higher coin values.

Who Will Enjoy Thunder Strike XXL?

Thunder Strike XXL keeps the rules short: fruit symbols on 15 lines, cash coins, a lightning collector and a respin round with four jackpots. The tall 3x5 grid and the sticky collectors on the middle reel make it feel different from the usual 3x3 coin games, while the 70x and 200x buys give direct access to the main feature. It is a good choice for fans of Hold and Win slots and quick, jackpot-focused sessions.

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